The projector apparatuses known in the related art include those configured as compact units and mounted on digital cameras and the like (see, for instance, patent references 1 and 2). When guiding illuminating light to be used for image read, to an image display device, a projector apparatus converts the illuminating light originating from a light source to parallel light via a condenser lens and obtains polarized light as the parallel light travels through a polarization beam splitter (PBS). The image display device may be constituted with, for instance, a rectangular reflection-type liquid crystal display element.    Patent reference 1: Japanese Laid Open Patent Publication No. 2002-287084    Patent reference 2: Japanese Laid Open Patent Publication No. 2005-250392